Edible Soil
A lesson based on the book, The Soil Neighborhood, by Dan Yunk and Steve Swaffar.
America’s food supply is safe, affordable and abundant but misunderstood by the public. Kansas Farm
Bureau seeks to improve consumer knowledge of the importance of farming and ranching through the
Kailey’s Ag Adventure Series, of which this book is a part.
BACKGROUND INFORMATION:
How Soil is Formed:
It takes soil several years to form from a starting point of bedrock or
parent material. As time goes by, good quality soil will develop four or
more distinct layers. Soil will be composed of inorganic and organic
components such as minerals, air, water and plant and animal material.
At the surface is the O horizon, a layer of organic material, usually partly
decomposed, also called residue or leaf litter.
Next is the A horizon, known as topsoil. Most plant roots grow in this
layer and it holds most of the soil’s nutrients.
The B horizon, or subsoil, contains sand, silt and clay. Soils are
classified according to their texture. Soil texture is determined by the
amount of sand, silt or clay in the soil.
The C horizon is partially broken down bedrock. The last layer is the R
horizon. These layers make up the parent material. Some classification
schemes add other layers, but these are the simplest forms. The deeper
the O and A layers are, the richer the soil. Soil profiles vary greatly from
location to location.
For this activity we use the terms: parent material, subsoil, topsoil, and
residue.
How Soil is Lost:
The loss of soil is called erosion. Erosion occurs when soil is moved by
water, wind or gravity. Several conservation practices that help prevent
soil erosion include: planting trees to slow the speed of the wind,
securing topsoil with plant roots, and using terraces to carry run-off water
away from bare topsoil. There are many methods farmers and
conservationists have utilized to protect the fertile, productive soil in
Kansas. They include reducing the frequency of tillage, planting cover
crops during dormant seasons, farming along the contour of the land
(contour farming), planting crops in a strip cropping pattern, utilizing crop
rotations, planting and maintaining shelterbelts (windbreaks), and
planting grass waterways and terraces.
LEVEL: 3rd-4th grade
SUBJECTS/STANDARDS:
Subject: Science
Standard: Earth's Systems:
Processes that Shape the
Earth
Benchmark: Identify
evidence from patterns in
rock formations and fossils in
rock layers for changes in a
landscape over time to
support an explanation for
those changes.
Indicator: Students identify
layers of soil in soil profile.
ACTIVITY DESCRIPTION:
Students will use edible
ingredients to create a soil
profile. They will learn about
the different layers of soil
and the components that
make up a soil profile.
photo from www.indulgy.com
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ACTIVITY:
Prepare Ahead:
1. Purchase ingredients for Edible Soil Profile.
2. Prepare the pudding according to the directions on the package.
3. Place chocolate sandwich cookies into a sealed plastic bag and
crush using a rolling pin. Alternatively, use a food processor to crush
the cookies.
STUDENT LEARNING
Students will:
- Identify the layers of a soil profile.
- Recognize three factors that
cause soil erosion.
- Recognize four methods Kansas
farmers use to protect against
erosion.
ESTIMATED
TEACHING TIME: 30 minutes; 10
minutes prep time
4. Set out 5 bowls and spoons with the ingredients to be served from.
NEW VOCABULARY:
6. Arrange ingredients along a long table buffet style in order from the
bottom to the top of their soil profile ingredients.
Erosion
Parent Material
Subsoil
Topsoil
Residue
7. Label each ingredient as its appropriate soil layer.
MATERIALS NEEDED:
5. Have plastic gloves for person serving gummy worms.
Procedure:
1. Have students wash their hands to prepare for the lesson.
2. Review the layers of a soil profile, and tell the students they will be
making their own edible soil profile.
3. Demonstrate how each soil layer is represented and what the profile
should look like. You may have the attached diagram available for
review.
- Clear plastic cups for each
student
- Spoons
- Candy coated chocolate (M&M’s)
- 2 -3 boxes of chocolate pudding
(prepared)
- Chocolate sandwich cookies,
crushed
- ½ cup coconut
- Gummy worms for each student
- 5 serving bowls
- Plastic gloves
- Labels for each soil layer
ingredient
4. Place each soil layer ingredient by its appropriate label
a. candy coated chocolate = ‘Parent Material’
b. chocolate pudding = ‘Subsoil’
c. crushed chocolate sandwich cookies = ‘Topsoil’
d. coconut = ‘Residue’
e. gummy worms = ‘Earthworms’ or ‘Organisms’.
5. Demonstrate making the soil horizons of your edible soil.
6. Put a spoonful of candy-coated chocolates into the bottom of an individual cup; discuss what Parent
Material is. Repeat this procedure with the pudding (Subsoil), followed by cookie crumbs (Topsoil),
coconut (Residue) and finally a gummy worm (Earthworms or organisms).
7. Allow each student to prepare their own Edible Soil. Enjoy!
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TEACHER’S NOTES:
Discussion Questions:
1. Which layer is represented by the candy coated chocolate? (Parent Material)
2. Which layer does the pudding mixture represent? (Subsoil)
3. Which layer is represented by the crushed cookies? (Topsoil)
4. Why are soils with deeper topsoil layers more productive? (More room for plant root growth and
development, and also more nutrient storage capacity)
5. What did the coconut layer represent? (Residue)
6. What types of organisms live in soil and aid in soil production? (Earthworms, bugs, grubs, etc.)
7. Where have you seen the four soil layers exposed? (In a creek bed or along the side of the road
where the hill was cut away, etc.)
8. Where have you seen erosion? (Ditches in a field or road, soil blowing during dry summer,
canyon)
9. Describe how the erosion looked and tell if it was it done by wind, water or gravity.
10. How might it have been prevented?
11. What are at least four conservational practices farmers are currently doing to decrease soil
erosion? (Reducing the frequency of tillage, planting cover crops during dormant seasons,
farming along the contour of the land (contour farming), planting crops in a strip cropping
pattern, utilizing crop rotations, planting and maintaining shelterbelts (windbreaks), and planting
grass waterways and terraces)
“Civilization itself
rests upon the soil”
-Thomas Jefferson
Photo from www.marlimillerphoto.com
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Student Name
Date
Soil Profile
Direcons: Label the four layers of soil using the words from the word bank.
1.
2.
3.
4.
Word Bank
Residue
Subsoil
Parent Material
Topsoil
Worksheet 1
Student Name
Date
Soil in Your Life
Have you ever thought about how important soil is in your daily life? It grows the fibers that
make your clothes, produces the crops that feed you, makes food for livestock that will be
eaten for meat, and lots more.
Directions: In the big circle surrounding “Soil,” list everything you have done today,
everything you have eaten, and any products you may have used.
On the lines provided, write down how your listed items are connected to the soil.
Soil
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Worksheet 2